Prof. Ulf Leonhardt from the Weizmann Institute of Science in Israel spent one month as AIANI-TIWAG Guest Professor at the Institute of Theoretical Physics at the University of Innsbruck.Prof. Leonhardt held a lecture series on the “Quantum Vacuum” and his inspiring talks and presentatios drew a large audience to the lecture halls, ranging from master students, PhD’s to Postdocs and several faculty members. They also sparked a great number of discussions, laboratory visits and emerging future collaborations. The Institute of Theoretical Physics thanks TIWAG and AIANI for making this fruitful and inspiring visit possible.

Prof. Dan Yakir from the Department of Earth and Planetary Sciences at the Weizmann Institute of Science came as “AIANI Fellow” to the University of Innsbruck. The overarching topic of the visit of Prof. Yakir in the Biometeorology research group at the Institute of Ecology was the common interest in the biosphere-atmosphere exchange of the trace gas carbonyl sulfide. During his visit, Prof. Yakir gave a public seminar lecture entitled “Forest-climate interactions: Perspectives from the semi-arid region” and participated in weekly Biometeorology group meetings. More specifically, Prof. Yakir engaged in discussions with Katharina Gerdel, a PhD student who recently (March-May 2017) participated in a joint field campaign at Yatir forest in Israel. Prof. Yakir also engaged in discussions with two other PhD students, Florian Kitz and Felix Spielmann, whose PhD projects also revolve around carbonyl sulfide, however at different field sites.For the future, the research group intends to continue the collaboration with Prof. Yakir. In the first place, they aim at publishing the results of the joint measurement campaign within the

frame of the dissertation of Katharina Gerdel – they expect two publications to result from these data. In addition, they have discussed several options for other joint publications and further possibilities for joint measurements. Prof. Yakirs stay was supported by "Land Tirol".